Researchers have discovered a new antibiotics with the potential to treat fungal infections. Design by Medical News Today; photography by Maskot/Getty Images and Catherine McQueen/Getty Images.
- After discovering the bacterium Dickeya solani more than a decade ago, researchers found a compound that could help treat a fungus that causes human infections.
- Researchers found the compound while analysing the microbe’s genes.
- The antibiotic compound salinomycin comes from a microbe found in potatoes.
- Many of the microorganisms that antibiotics are derived from are originally found in soil.
In a new study published in mBio, scientists in Europe discovered a new antibiotic called salinomycin. Not only does salinomycin target a fungus in humans that can cause infections, but it may also be beneficial for treating certain plant fungi.
Research is in the preliminary stages, but the authors hope that further clinical studies may lead to the antibiotic being used in clinical and agricultural settings.
Antibiotics for fungal infections
According to the Centers for Disease Control and PreventionTrusted Source (CDC), antibiotics are “medicines that fight infections caused by bacteria in humans and animals by either killing the bacteria or making it difficult for the bacteria to grow and multiply.”
By slowing down bacteria growth in the body with antibiotics, it becomes easier for the immune system to attack the infection. While antibiotics are helpful with treating infections caused by bacteria or a fungus, they are not used to treat viruses.
Some prescribed antibiotics often include azithromycin, amoxicillin, penicillin, and cephalexin.
In addition to traditional antibiotics, there is another class called antifungal antibiotics, which target fungi. The National Library of MedicineTrusted Source notes that “fungi are unicellular or multicellular eukaryotic organisms that exist in all environments worldwide.”
While there are millions of types of fungi, according to the CDCTrusted Source, only a few hundred harm humans. Some common fungal diseases include nail infections, eye infections, pneumocystis pneumonia, and vaginal candidiasis.
Typically fungal diseases are simple to treat, but occasionally they lead to more serious issues such as asthma, lung infections, and meningitis.
As Dr. Tom Chiller comments in The Fungus Among Us podcast, “ there are fungal diseases that can be invasive — in other words, they can get into our bodies either via the lung or via some other route and can get into our bloodstream, get into our organs, and really cause serious damage.”
Discovering a new contender: Solanimycin
Just because an antibiotic is useful in treating bacteria or fungi does not mean it will be useful forever, as these pathogens can mutate and become resistant over time. This is the basis for the research that led to the study of salinomycin.
“The increasing emergence of drug-resistant fungal infections has necessitated a search for new compounds capable of combating fungal pathogens of plants, animals, and humans,” write the study authors.
Researchers first discovered the bacterium Dickeya solani on tomatoes in 2005–2006. Subsequent research showed that it is more commonly found in potato plants.
The bacterium causes disease in plants that can slow down plant growth or even kill them, making it a major threat to crops.
While initially researching D. solani, scientists learned that certain gene clusters produce an antibiotic called oocydin A.
The researchers continued studying D. solani over the years and noticed some changes. The authors noted that some mutations lost properties “but still retained strong activity against several plant-pathogenic fungi.”
Based on that realisation, the researchers suspected that they might be able to find another antibiotic. After studying the D. solani genome, they discovered the antifungal antibiotic they named salinomycin.
Uses of solanimycin Antibiotics
The study authors were primarily interested in how salinomycin worked against plant fungi and learned it was “active against around 70%” of the plant fungi they tested.
Additionally, they learned that salinomycin is effective in treating Candida albicans.
Candida is found both inside people’s bodies and on their skin. Whenever there is an overgrowth, this can lead to infections.
The most common Candida infections include urinary infections, genital infections, and oral thrush. According to the CDC Trusted Source, Candida can cause lung infection, Valley fever, and histoplasmosis.
While antifungal antibiotics are available, salinomycin could add to the tools available to treat infections.
While most people with infections caused by Candida should recover without issue, some people have more difficulty with these infections. People with weakened immune systems are at a higher risk for infections in general and have a more difficult time fighting them off.
People with cancer or HIV or taking medications that lower the immune system can develop life-threatening illnesses stemming from these infections and could benefit from discovering a new antibiotic.
“We have to be open to the exploration of everything that’s out there to find new antibiotics,” says study co-author Dr. Miguel Matilla.
Dr. Matilla is a molecular microbiologist at Zaidín Experimental Station in Granada, Spain.
“Fungal infections represent a major clinical, agricultural, and food security threat worldwide, which is accentuated due to the difficult treatment of these infections,” write the authors.
What do other experts think?
“Overall, it’s encouraging to read the research done involving the novel antifungal, solanimycin,” commented Dr. Peak. “Even though it’s too early to know the clinical impact, the fact that solanimycin was active against Candida albicans — the most common source of fungal infections in humans — is a positive sign.”
Dr. Peak is the vice president of the Clinical Pharmacy program for Sedgwick, a healthcare claims company based in Memphis, TN.
Dr. Peak went on to elaborate on the importance of continuing such research:
“A lot of focus on drug resistance has historically been centred around antibiotics, so it is good to see that science is also discovering new potential treatments for fungal infections. Hopefully, this will bring more attention to the fact that antifungal resistance is an increasing threat as well,” he added.